Animals sense vibrations, mostly via the ear. The human ear is able to sense vibrations over a wide range of frequencies as audible sound.
In the audible range, acoustic vibrations are experienced as sounds. Quality speakers are required for quality reproduction of music. To provide audible sensations in the low bass, very large speakers are required. Personal earphones are not effective in providing deep notes in the bass section of the audible spectrum i.e. in the range of <250 Hz. The bass signals are only weakly picked up via the earphones, and this is one reason why people tend to listen to music via earphones at high volume, which is generally damaging to the ears. In a concert hall, some of the bass is sensed via the feet picking up vibrations of the floor, and the body sensing vibrations of the seat.
Similarly, to enable individuals to experience bass, for example, when listening to a DVD, an MP3, MP4 or smart-phone via earphones, mechanical vibrators may be attached to the body. Preferred locations are on acoustic meridians, such as near the sternum and the base of the spine, or on the legs or feet. This can provide sensations that are felt rather than heard, and which can provide or contribute to an immersive effect, particularly when provided with and synchronized with audible and visible sensations via earphones and screens. Thus, music, electronic games and movies may be enhanced by providing low frequency signals to the body.
Electromechanical vibrators that are capable of providing low frequency vibrations may comprise eccentric motors or pistons that consist of solenoid and magnets that are attracted and repelled by alternating currents in the solenoid.
In previously submitted patent applications, WO 2012/028973 “Personal Media Playing System” and WO 2012/029009 titled “A Wearable Vibration Device” a vibration device and its use for enhancing the experience of media was discussed.
The device was used for receiving low frequency electronic signals and for generating low frequency vibrations, particularly for enhancing the enjoyment of music, games and movies to a wearer.
The device, may be pinned to the body, and can oscillate at low frequencies to provide low frequency vibrations that provide a sensation of base signals. The signals are sensed where the device is positioned. If the device is placed on a rigid base, the vibrations may be felt anywhere on that base. If attached to a flexible fabric such as to an article of clothing, the signals are generally damped and only felt in the immediate vicinity of the device, which generally needs to be held against the body.
High quality vibrating devices capable of providing large amplitude vibrations over a range of frequencies are expensive. Sometimes, there is a desire to provide signals selectively to different locations. However, each single high quality vibrating transducer is expensive.